Micrometer-gage.



M. L. ROLLIER.

MICROMETER GAGE.

APPLICATION FILED NOV. 19. 1913.

1 1 58,72 1 Patented Nov. 2, 1915.

2 SHEETSSHEET 1.

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MARIE LOUIS ROLLIER, OF VANNES, FRANCE, ASSIGNOR TO CHARLES IVIARIE ANTOINE RIVOAL, OF PARIS, FRANCE.

1 MIonoMErnn-GAG'E.

Application fi1ed Noveniber lti, 1913. Serial No. 801,871;

To all whom it may concern Be it known that I, MARIE LoUIs ROLLIER, a citizen of the Republic of France, residing atVannes, Seine, France, have invented certain new and useful Micrometer-Gages, of whichthe following is a specification.

This invention relates to improved micrometer gages for taking accurate measurements, the said improvements tending to secure with more precise results easier and quicker manipulation.

A 'micrometer gage in accordance with this invention comprises a movable dial arranged in front of a vernier, and caused to berotated by means of a plunger carrying a roller which bears on a cam whose contour has the shape of an Archimedean spiral, the said cam being mounted on the same spindle as the dial so that when the plunger is acted upon,-the roller permits the rotation of the cam-which operates the dial.

The object of the invention consists essentially,.in doing away with the thrust of the roller on the cam, by moving the said cam by means of a spiral spring so that the roller carried by the plunger has only to maintain the cam in posltion against the action of the spiral spring, and the said cam Will, when it is released by depressing the plunger, rotate automatically While remaining in contact with the roller. This arrangement, which in reality is an indirect control While at the same time facilitating the manipulation and permitting'of obtaining a greater precision, obviates a premature wear of the cam and the roller and any tendency to Which may occur. 7

In order to increase the range of the measurements of which the is susceptible the plunger is made in two parts, one of which can slide Within the other and be fixed in position by a bayonet joint arrange-- Specification of Letters Patent.

. fication of original position, the spiral spring Patented Nov. a, 15915.

case which contains the mechanism and shows the dial and Vernier. Figs. 5 and 6 show respectively an elevation and horizontal section through line 2-2 of Fig. 5, of the sliding plunger, while Fig. 7 is a modithe said plunger.

The cam a, the contour of which is an Archimedean spiral, is subjected to the actionof a spiral spring 6 (Figs. 2 and 3) secured at one end to the said cam and at the other end to the arbor c on which the said cam is mounted and tending to turn the cam in the direction of the arrow 1 (Fig. 1). A roller d secured to the end of carried by the plunger 7 normally engages (that is when the spiral spring is under ten- S1011) 1n a recess 9 provided in the cam a. A sprlng it connecting the arm 6 to the easing a of the gage maintains the plunger and cam, through the medium of the roller d, in theposition shown in the drawing, which position corresponds to the zero mark of the gage.

It will be readily understood that when the plunger is depressed the spring A is eX- tended and the roller d gradually releases the cam a which turns automatically under theaction of the spiral maining in contact with the roller, until the the roller (Z assumes the position (1, so that while a measurement is being taken, the only pressure exerted by the arm on the roller is that due to the twisting moment of the spring. lVhen the plunger is released the Spring it returns automatically to its initial position and the roller cl following the contour of the cam causes the latter to turn in the reverse direction and come back to its being thereby Woundup. The operator reads on the dial j and Vernier 70 (Fig. 4) the measurement corresponding to the extent to which the plunger has moved downward.

The plunger consists preferably of two parts which permit of varying its stroke and consequently altering as desired the range of measurements of the gage. It c0nsists of a sheath 7 slotted at r so as to allow the passage of the part of the cam 42/. which has the larger radius and in the said sheath slides a rod Z which constitutes the plunger proper (Figs. 5, 6, 7). The sheath f is provided at its upper part with the groove m of a bayonet joint while the rod Z has a an arm 6 spring Z) while relug n, which can move in this groove. In the normal position, the lug n being out of the groove bears on the upper part of the sheath the edge of which presents a slope while at the same time a washer 0 on the lower end of the rod Z bears likewise on the other end of this sheath so that the rod is maintained in a fixed position, the lug n being jammed on the aforesaid slope so as to press thewasher 0 against the sheath, thereby avoiding all play and taking up the wear.

The groove m can beprovided either with a single notch 79 at one end of the said groove as shown in Fig. 5,0r with several notches at various parts of its length, for instance it may be arranged as shown in Fig. 7, according to which it is provided with a notch p at the middle of its length opening into the slotted part of the sheath. The notched part 39 and the lower edge of the part f of the sheath are constituted as slope and counter slope so as to cause either the Washer 01- the underside of theplungerto bear on the sheath as hereinbefore explained and consequently do away with all play. 1

By displacing the rod Z so that the lug 7;

slides in the groove m and catching this lug into the notch 9 or below the portion 7 of the sheath at 20, the part of the plunger forming the movable measuring end of the gage is more or less lengthened, the initial space comprised between this movable measuring point and the fixed measuring part 9 is accordingly modified so that the range of measurements of which the gage is susceptible can be varied as desired. The casing is shown internally of circular form and the frame of horse-shoe shape. A set screw on is shown for holding the plunger in an advanced position either for ease in transportation or to enable the device to be used as a fixed gage.

What I claim is 1. In a micrometer gage, the combination with an indicating device, ofa cam fast therewith, spring means continuously tending to turn the cam in one direction, a spring retracted-plunger provided "Wlfih an engaging face continuously in contact with the cam, the cam being of such contour that extension of the plunger against the action of its spring permits the cam to move for-v wardly responsive to its spring and retra'ction of the plunger responsive to its spring moves the cam backwardly against the action of its spring.

2. Ina micrometerv gage the combination with a cam, of dial movable therewith,'a spring for turning the dial forwardly, a

plunger having an engaging face for en-' gaging the cam and permitting the forward movement of the dial upon. its depression and for returningthe cam and winding up the cam. spring upon its retraction.

3.- In a micrometer gage the combination with a cam, of a dial movable therewith, a spring for turning the dial forwardly, a plunger having an engaging face for engaging the cam and permitting the forward movement of the dial upon .its depression and for returning the cam and winding up the cam spring upon its retraction, and

1 s rin means for retractin the lun 'er.

4:. In amicrometer gage the combination cam, spring means for rotating the cam in the direction in which its radius de-' creases, a spring pressed actuator engaging the contour of; the cam and holding it against the influence of its spring and located in position'for releasing the cam to the influence of its spring uponits depreswith a cam having the contour ofan Arch i .7 imedean spiral, of a dial movable with the sion, and for returning the cam and wind- MARIE LOUISROLLIER.

Witnesses HANSON C. Ooxn, GABRIEL BELLIARD.

copiesof this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, 110.

I have hereunto 

